Pulse oximetry is a widely accepted continuous and non-invasive method of measuring the level of arterial oxygen saturation in blood. A typical pulse oximetry system has a sensor, a patient monitor and a patient cable. The sensor is placed on a patient fleshy tissue site, usually on the fingertip for adults and the hand or foot for neonates and connected to the patient monitor via the patient cable. The sensor provides a sensor signal detected from the patient tissue site to the patient monitor. The patient monitor displays the calculated data as a percentage value for arterial oxygen saturation (SpO2), as a pulse rate (PR) and as a pulse waveform (plethysmograph or “pleth”).